Does My Dog Have Mange?

Demodectic mange, also called "demodicosis," is caused by a microscopic mite of the Demodex genus. All dogs raised normally by their mothers possess this mite as mites are transferred from mother to pup via cuddling during the first few days of life. Most dogs live in harmony with their mites, never suffering any consequences from being parasitized. If, however, conditions change to upset the natural equilibrium (such as some kind of suppression of the dog's immune system), the Demodex mites may "gain the upper hand." The mites proliferate and can cause serious skin disease.

Demodectic mange (unlike Sarcoptic mange) is not considered a contagious disease and isolation of affected dogs is generally not considered necessary. That said, there are some circumstances under which the mites could spread from one dog to another.

Classically Demodex mites have been felt to only be transferable from mother to newborn pup. After the pup is a week or so old, it has developed enough immunity so that infection is no longer possible. In other words, after age one week or so, a dog will not longer accept new mites on its body.

Recently this idea has been challenged as occasionally multiple unrelated dogs break with demodicosis in the same household. It is not clear if some species of Demodex are more contagious than others or if some contagion is possible under certain circumstances. Current thinking is that mites actually can be transferred from one dog to another but as

long as the dog is healthy, the mites simply add into the dog's natural mite population and no skin disease results. Isolation of dogs with even the most severe demodicosis is still felt to be unnecessary; though, in rare circumstances contagion is possible. While there are still assorted theories about dog to dog transmission of Demodex mites, there is no question that mites cannot be transmitted to humans or to cats.

• Mites live inside hair follicles -- a difficult place for miticides (chemicals that kill mites) to reach.
   
• Mites are a normal residents of dog skin; it is only in some individual dogs that mites cause problems.

The younger the dog, the better the chance of cure. Most dogs under one year and a half years of age, recovery completely from generalized demodicosis. In many cases of adult-onset demodicosis, the disease is controlled with treatment but cure is not always possible. Some cases can never be controlled. As always early diagnosis and treatment give the best chance of a complete cure.